Do I need aluminum coil stock over fiber cement fascia board?
MikeonLI
| Posted in General Questions on
Hi everyone
Homeowner in Long Island ny. I’m thinking of getting fiber cement siding. I’ve seen online that some contractors, when using fiber cement trim, specify aluminum coil stock over the fascia board. Does anyone have any experience with that? I’m assuming the gutter gets wet and they don’t want it to be in prolonged contact with the fiber cement fascia? Any insight is appreciated!
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Search and download construction details
Replies
I haven't installed fiber-cement trim but from everything I've heard, builders often don't like it because it's heavy and brittle. What I have seen on many projects is framing lumber, or other relatively low-cost lumber, used as a base, with aluminum trim coil bent over it for a long-lasting "cover." There may be moisture-related reasons to avoid fiber-cement for fascias but it's made for the application so I don't think that would be an issue.
Thanks for the comments about the brittle and difficult to handle aspect of the trim. I would like to use the pre-painted fiber cement for the siding. Because of the style of the house, the rakes, corners, and soffits etc should match the siding color.
Unfortunately, my contractor does not want to do all that painting to color match the siding if I use a different trim besides fiber cement, like pvc, for the corners, rakes and soffits. It would add a huge expense.
the trim around the windows and doors, however, could be a different color to contrast with the siding and I can use pre-painted pvc trim there.
My architect does not like the appearance of aluminum coil stock for the rakes, corners and soffits even if it color matched the siding. Trying to gather all the feedback here.
If it can’t be painted, and I don’t use the aluminum coil stock, I just don’t see any other option other than the pre-painted fiber cement for all the trim, except the trim around the windows and doors, but very open to other ideas!
I also don't like how coil stock trim looks, but it's very popular where I am in rural Maine. Coil stock can be painted. If your builder wants to install cement-based trim because it's prepainted, I don't see a reason to argue about it. I do recommend making sure there is at least a 1-year warranty on the product and installation though.
Thanks Michael for the helpful response. I’ll make sure there is a warranty on the product and the installation.
MikeonLI,
If you are going to cover the fascias with coil stock, I would use another substrate as cement based materials aren't great in that application. My preference would be MPS pressure treated wood.
Thanks Malcom. So I guess you suggest the aluminum coil stock covering the fascias for this application?
Mike,
I only use fascias on gable ends where they are a visible part of the facade. We are lucky here in that we have access to dry, good looking MPS pt lumber which takes stain or paint well. So that's what I use there, but I'd be comfortable cement-based materials too. I agree with your architect: If they are visible, I don't like the look of coil-stock.
At the eaves when there will be gutters, I use 5" fascia-gutters attached directly onto the 2"x4" sub-fascia as I don't think a finished fascia of any material adds much there except maintenance. If I was going to use one I'd probably have it covered by coil stock.
The attached photo shows both conditions on my house. Pt fascias above and 5" fascia gutters below
Malcolm, thanks for the helpful responses and the photos. I really appreciate it.
Malcolm, I don't recall hearing about MPS lumber--it looks like this is it: https://microprosienna.com/. It's not available here in New England, unfortunately.
Michael,
I think MPS is the brand name in Canada. The process is MCA. It may be available there under that name. Unlike the dreaded ACQ it doesn't eat fasteners, and isn't soaking wet when you buy it, so you can coat it right away.